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QICO2 Indoor Carbon Dioxide Metric Analysis Tool

Metadata Updated: July 29, 2022

Indoor carbon dioxide (CO2) concentrations have been used for decades to evaluate indoor air quality (IAQ) and ventilation, and more recently in discussions of the risk of airborne infectious disease transmission. However, many applications of indoor CO2 measurement reflect a lack of understanding of the connection between indoor CO2 levels, ventilation and IAQ. In many cases, an indoor concentration of 1000 ppmv has been used as a metric of IAQ and ventilation without an understanding of its basis or significance. After many years trying to dissuade practitioners and researchers from using this or some other single concentration as an overall metric of ventilation and IAQ, an approach has been developed to determine a space-specific CO2 level that can be used as an indicator of the outdoor ventilation rate. The concept is to estimate the CO2 concentration that would be expected in a specific space given its intended or expected ventilation rate per person, the number of occupants and the rate at which they generate CO2. A calculation method is described for estimating the CO2 concentration in a given space at selected times after occupancy starts, which provides a more meaningful metric than a single value for all spaces. An online tool (QICO2, Quick Indoor CO2) has been developed to perform these calculations, and this report also contains a User Guide for that tool.

Access & Use Information

Public: This dataset is intended for public access and use. License: See this page for license information.

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Metadata Created Date June 22, 2022
Metadata Updated Date July 29, 2022
Data Update Frequency irregular

Metadata Source

Harvested from NIST

Additional Metadata

Resource Type Dataset
Metadata Created Date June 22, 2022
Metadata Updated Date July 29, 2022
Publisher National Institute of Standards and Technology
Identifier ark:/88434/mds2-2562
Data First Published 2022-04-01
Language en
Data Last Modified 2022-03-01 00:00:00
Category Buildings and Construction:Indoor air quality
Public Access Level public
Data Update Frequency irregular
Bureau Code 006:55
Metadata Context
Schema Version
Catalog Describedby
Harvest Object Id cd681850-0bc4-4532-8126-609bfd47d9df
Harvest Source Id 74e175d9-66b3-4323-ac98-e2a90eeb93c0
Harvest Source Title NIST
Homepage URL
Program Code 006:045
Related Documents
Source Datajson Identifier True
Source Hash a0b646eb3e0331a89d341db21a2a603c0e87737a
Source Schema Version 1.1

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